.photo_gallery{	float:left; padding:5px; margin:5px; border:1px solid #ccc;}
.photo_gallery img{ padding:0px; margin:10px;}
/*

* {box-sizing: border-box}
*/
 Container needed to position the overlay. Adjust the width as needed 
.container {
  position: relative;
   max-width: 300px;
}

/* Make the image to responsive 
.image {
  
}
*/
/* The overlay effect - lays on top of the container and over the image */
.overlay {
  position: absolute; 
  bottom: 0; 
  background: rgb(0, 0, 0);
  background: rgba(0, 0, 0, 0.5); /* Black see-through */
  color: #f1f1f1; 
  transition: .5s ease;
  opacity:0;
  color: white;
  font-size: 20px;
  padding: 30px;
  text-align: center;
  width:250px;
}

/* When you mouse over the container, fade in the overlay title */
.container:hover .overlay {
  opacity: 1;
}